GIS Tutorial 1 Lecture 4 Geodatabases

Outline  Data types  Geodatabases  Data table joins  Spatial joins  Field calculator  Calculate geometry  ArcCatalog functions 2 GIS TUTORIAL 1 - Basic Workbook

DATA TYPES Lecture 4 3 GIS TUTORIAL 1 - Basic Workbook

Directly loadable data types  dBase (.dbf)  Text with comma (.csv) or tab-separated values (.txt)  Microsoft Access (.mdb)  Microsoft Excel (.xls) 4 GIS TUTORIAL 1 - Basic Workbook

Data table formats  First row must have attribute names with self-documenting labels  (e.g. Pop5To17, Area)  Usual naming convention  first character is a letter  remaining characters be any letters, digits, or the underscore character  All additional rows of a data table need to contain attribute values  None of the rows can be sums, averages, or other statistics of raw data rows 5 GIS TUTORIAL 1 - Basic Workbook

Data table formats  dBase field names  Maximum 10 characters 6 GIS TUTORIAL 1 - Basic Workbook

GEODATABASES Lecture 4 7 GIS TUTORIAL 1 - Basic Workbook

Geodatabase types Manages features and tables inside a database management system  File geodatabase  stores datasets in a folder of files  each dataset a file up to 1 TB in size  can be used across platforms  can be compressed and encrypted for read-only, secure use  ESRI’s recommended choice 8 GIS TUTORIAL 1 - Basic Workbook

Geodatabase types  Personal geodatabase  stores datasets in a Microsoft Access.mdb file  storage sizes between 250 and 500 MB  limited to 2GB  only supported on Windows  ArcSDE geodatabase  stores datasets in a number of optional DBMSs:  IBM DB2, IBM Informix, Microsoft SQL Server, Oracle, or PostgreSQL  unlimited size and users 9 GIS TUTORIAL 1 - Basic Workbook

New file geodatabase ArcCatalog 10 GIS TUTORIAL 1 - Basic Workbook

Import into geodatabase 11 GIS TUTORIAL 1 - Basic Workbook Shapefile features

Import into geodatabase  Tables 12 GIS TUTORIAL 1 - Basic Workbook

Export from geodatabase 13 GIS TUTORIAL 1 - Basic Workbook

Compact geodatabases  File and personal geodatabases  Reduces size and improves performance  Compact personal geodatabases > 250 MB.  Geodatabases with frequent data entry, deletion, or general editing  Open geodatabases in ArcMap cannot be compacted  remove any layers with a source table or feature class in that database from the TOC 14 GIS TUTORIAL 1 - Basic Workbook

Compress geodatabases  File geodatabases  Once compressed, a feature class or table is read-only and cannot be edited  Compression is ideally suited to mature datasets that do not require further editing  Compressed dataset can be uncompressed to return it to its original, read-write format 15 GIS TUTORIAL 1 - Basic Workbook

View geodatabases  Cannot identify names in Windows Explorer  Must use ArcCatalog 16 GIS TUTORIAL 1 - Basic Workbook

DATA TABLE JOINS Lecture 4 17 GIS TUTORIAL 1 - Basic Workbook

Data table joins  Putting two tables together to make one table  Join two tables one-to-one by row  Must have the same values and data types 18 GIS TUTORIAL 1 - Basic Workbook

Join example  Housing heating fuel study for U.S. Counties  Source: U.S. Census  Data table: Census SF3 table for heating fuel by county  Map Features: County polygons 19 GIS TUTORIAL 1 - Basic Workbook

Data table  Heating fuel table (Excel spreadsheet) 20 GIS TUTORIAL 1 - Basic Workbook

Data table  Heating fuel table data dictionary  H040001: Occupied housing units: House heating fuel; TOTAL Units  H040002: Occupied housing units: House heating fuel; Utility gas  H040003: Occupied housing units: House heating fuel; Bottled; tank; or LP gas  H040004: Occupied housing units: House heating fuel; Electricity  H040005: Occupied housing units: House heating fuel; Fuel oil; kerosene; etc.  H040006: Occupied housing units: House heating fuel; Coal or coke  H040007: Occupied housing units: House heating fuel; Wood  H040008: Occupied housing units: House heating fuel; Solar energy  H040009: Occupied housing units: House heating fuel; Other fuel  H040010: Occupied housing units: House heating fuel; No fuel used 21 GIS TUTORIAL 1 - Basic Workbook

Feature class  County polygons 22 GIS TUTORIAL 1 - Basic Workbook

Add data and features to map 23 GIS TUTORIAL 1 - Basic Workbook

Open attribute tables  Find common attribute to join 24 GIS TUTORIAL 1 - Basic Workbook

Data problem  FIPS has leading zero and is a TEXT field.  GEO_ID2 is a NUMBER field with no leading zeros. 25 GIS TUTORIAL 1 - Basic Workbook FIPS GEO_ID

Data solution  Make a new NUMBER field in Counties attribute table and use field calculator to populate new field from old 26 GIS TUTORIAL 1 - Basic Workbook

Data solution  New FIPS_NUM is same as GEO_ID2 and ready to join 27 GIS TUTORIAL 1 - Basic Workbook

Join tables 28 GIS TUTORIAL 1 - Basic Workbook

Join result  Heating fuel data is now listed for every county in the USCounties feature attribute table 29 GIS TUTORIAL 1 - Basic Workbook

Permanent joins  Joins are temporary and can be removed  Export data to make joins permanent 30 GIS TUTORIAL 1 - Basic Workbook

Choropleth map result 31 GIS TUTORIAL 1 - Basic Workbook

SPATIAL JOINS Lecture 4 32 GIS TUTORIAL 1 - Basic Workbook

Spatial join example  You have census block group centroids with housing fuel data  You want to know housing fuel data by neighborhoods  No attributes in common  Spatial join needed 33 GIS TUTORIAL 1 - Basic Workbook

Spatial joins  Points to polygons  Spatially joins points (block centroids) within polygons (neighborhoods)  Joins using “shape” (not attribute field) 34 GIS TUTORIAL 1 - Basic Workbook

Spatial joins  Right click polygon layer (neighborhoods) 35 GIS TUTORIAL 1 - Basic Workbook

Join result  New polygon feature 36 GIS TUTORIAL 1 - Basic Workbook

Join result  Counts and sums 37 GIS TUTORIAL 1 - Basic Workbook

Count result  Number of points in each polygon 38 GIS TUTORIAL 1 - Basic Workbook

Sum result  Every block group centroid has associated data  (e.g. H040004, heating electricity shown in labels) 39 GIS TUTORIAL 1 - Basic Workbook

Sum result 40 GIS TUTORIAL 1 - Basic Workbook  One neighborhood example  Central business district  4 block groups  Housing units with electricity fuel ( )  Sum = 799

Choropleth map result (sum) 41 GIS TUTORIAL 1 - Basic Workbook

Choropleth map result (sum) 42 GIS TUTORIAL 1 - Basic Workbook

Other spatial joins  Polygons to points  Example: ATM robberies (points) need neighborhood name 43 GIS TUTORIAL 1 - Basic Workbook

Polygon to point join result  Neighborhood name shows on each point 44 GIS TUTORIAL 1 - Basic Workbook

Other spatial joins  Points to points  Example: What is the distance of a burglary to the nearest commercial property? 45 GIS TUTORIAL 1 - Basic Workbook

Point to point join result  Distance to nearest commercial property shows on each burglary point 46 GIS TUTORIAL 1 - Basic Workbook

FIELD CALCULATOR Lecture 4 47 GIS TUTORIAL 1 - Basic Workbook

Sample functions  Performs numeric calculations  Populates field  Concatenates text data 48 GIS TUTORIAL 1 - Basic Workbook

Field calculator functions  Calculate acres to square miles 49 GIS TUTORIAL 1 - Basic Workbook

Field calculator functions  Populate field with county name GIS TUTORIAL 1 - Basic Workbook 50

Field calculator functions  Concatenate house number and street fields GIS TUTORIAL 1 - Basic Workbook 51

CALCULATE GEOMETRY Lecture 4 52 GIS TUTORIAL 1 - Basic Workbook

Polygon/point centroids  Advanced calculations for finding a polygon’s point centroid 53 GIS TUTORIAL 1 - Basic Workbook

Calculate XY fields  Add new X and Y fields in the attribute table GIS TUTORIAL 1 - Basic Workbook 54

Calculate XY fields  Calculate geometry for X field, repeat for Y GIS TUTORIAL 1 - Basic Workbook 55

XY field results  Results are X and Y values based on map properties (e.g. Long/Lat or XY feet) 56 GIS TUTORIAL 1 - Basic Workbook

Export XY coordinates 57 GIS TUTORIAL 1 - Basic Workbook

Add XY data table 58 GIS TUTORIAL 1 - Basic Workbook

Export as shapefile  XY events should be exported as permanent shapefile or feature class 59 GIS TUTORIAL 1 - Basic Workbook

Calculate area  Add area field and calculate geometry GIS TUTORIAL 1 - Basic Workbook 60

Calculate perimeter  Add perimeter field and calculate script 61 GIS TUTORIAL 1 - Basic Workbook

Calculate length  Add length field and calculate script 62 GIS TUTORIAL 1 - Basic Workbook

ARCCATALOG FUNCTIONS Lecture 4 63 GIS TUTORIAL 1 - Basic Workbook

Basic functions  Copy, paste, rename, etc. 64 GIS TUTORIAL 1 - Basic Workbook

View and edit properties  Projections, fields, etc. 65 GIS TUTORIAL 1 - Basic Workbook

View metadata 66 GIS TUTORIAL 1 - Basic Workbook

Edit metadata 67 GIS TUTORIAL 1 - Basic Workbook

Create new files  Geodatabases, tables, features, etc. 68 GIS TUTORIAL 1 - Basic Workbook

Summary  Data types  Geodatabases  Data table joins  Spatial joins  Field calculator  Calculate geometry  ArcCatalog functions 69 GIS TUTORIAL 1 - Basic Workbook